A solar water heating system for tropical region is divided into two sub-systems which are a water storage system for collecting solar radiation and a water supply system with an auxiliary heat source. The water supply system may be further divided into subsystems of a concentrating system, a dispersing system and the combination thereof. The water storage system comprises a water storage tank, and the water supply system comprises a water supply tank. The water storage tank is connected to the water supply tank with connecting pipes. The function of the water storage system is only to store solar hot water, and the function of the water supply system is only to transfer and regulate solar hot water and supply users with water. A float valve or a water level sensor is used to automatically control the water inflow and outflow of the water storage tank and the water supply tank to be always in dynamic equilibrium, therefore the drying out of the collector and the shortage of the water supply for users are prevented. The advantages of the solar water heating system are that the system control and management is simplified and the idealization of investment and energy conservation is achieved.